P5

Question 1

define a scalar

Answer 1

only has magnitude

Question 2

define a vector

Answer 2

has magnitude and director
e.g. for an arrow -> length = magnitude
direction = direction

Question 3

vector quantities

Answer 3

force
velocity
displacement
acceleration
momentum

Question 4

scalar quantities

Answer 4

speed
distance
mass
temperature
time

Question 5

define a force

Answer 5

push or pull that acts on an object due to the interaction with another object
contact OR non-contact

Question 6

what needs to be the case for a contact force to act?

Answer 6

objects are physically touching

Question 7

what needs to be the case for a non-contact force to act?

Answer 7

objects are physically separated/not touching

Question 8

examples of contact forces

Answer 8

friction
air resistance
tension
normal contact force

Question 9

examples of non-contact forces

Answer 9

gravitational force
electrostatic force
magnetic force

Question 10

what happens when 2 objects interact/interaction pair?

Answer 10

when 2 objects interact a force is produced on both

interaction pair -> pair of equal and opposite forces acting on 2 interacting objects

Question 11

define weight

Answer 11

the force acting on an object due to gravity
newtons (N) -> newton meter
(changes with location)

Question 12

define mass

Answer 12

amount of matter in an object

kg -> mass balance

Question 13

what does the weight of an object depend on?

Answer 13

the gravitational field strength at the point where the object is (GFS = stronger when your closer to the mass causing the field and stronger for large masses)

Question 14

state the relationship between mass + weight

Answer 14

direct proportion

Question 15

GFS of earth?

Answer 15

9.8 N/kg

Question 16

weight equation?

Answer 16

weight (N) = mass (kg) x GFS (N/kg)

Question 17

define centre of mass

Answer 17

weight of an object conc. at a point

equal in all directions

Question 18

define resultant force

Answer 18

overall force acting on an object/point

in one direction

Question 19

what’s the RF if the forces are balanced?

Answer 19

0

Question 20

how is work done by a force/energy treansferred?

Answer 20

the force (RF) causes an object to move though a dist. 
(displacement)

Question 21

work done equation?

Answer 21

work done = force x dist.

Question 22

unit of work done?

Answer 22

joules (J)

Question 23

unit of dist.

Answer 23

metres (m)

Question 24

relationship between joules and newton-metres?

Answer 24

1 joule = 1 newton-metre

Question 25

what does work done against frictional forces cause?

Answer 25

rise in temp. of the object

Question 26

explain how work is done when you push something along a rough surface

Answer 26

work is done against frictional forces energy transferred to KE store of object as it moves some energy transferred to object's thermal stores -> friction causes overall temp. of object to increase

Question 27

what does it mean if an object is in equilibrium?

Answer 27

all forces acting on the object combine to give an RF of 0 | *CHECK pg.54*

Question 28

what 3 things ca happen when more than 1 force is applied to an object?

Answer 28

object: bends, stretches or compresses

Question 29

define elastically deformed

Answer 29

can go back to its original shape/length after the force is removed

Question 30

what is an elastic object?

Answer 30

can be elastically deformed

Question 31

define inelastically deformed

Answer 31

doesn't go back to its original shape/length after the force is removed

Question 32

what happens when a force stretches/compresses an object? | when elastically deformed?

Answer 32

work is done energy transferred to elastic potential energy store of object if elastically deformed, all energy transferred to EPE

Question 33

relationship between extension and force?

Answer 33

direct proportion

Question 34

force and extension equation?

Answer 34

force = k (spring constant) x e (extension)

Question 35

when does the direct proportion between force + extension stop?

Answer 35

when the force is too great and limit of proportionality is exceed